In structures for spray/aerosol, a spray can or an aerosol can contains, in addition to a content, liquefied gas such as LPG and butane or gas such as nitrogen, carbon dioxide, and air for ejecting the content. The content is ejected from a jet nozzle provided at an upper part of the can via an aerosol valve tube disposed in the can. Alternatively, a nozzle tube is further attached to the jet nozzle and the content is ejected from an ejection outlet provided at the leading end of the nozzle tube.
In ejecting the content in such a spray can or an aerosol can, the content and the gas are separated and ejected alternately. Consequently, the content is ejected discontinuously and failure in stable ejection is a problem.
Moreover, the amount of ejected content depends on the gas pressure in the can. The ejection occurs with a high pressure at the beginning and abruptly weakens as the gas pressure drops with time. Consequently, failure in constant ejection amount is also a problem.
In order to realize stable and constant ejection of the content, it is necessary to realize a constant gas pressure for a long time and mix the content and the gas well without separating or dividing them. Hence, various researches have been conducted hitherto for developing a gas to obtain a stable gas pressure for a long time or for structurally improving the spray can itself. However, such researches are still midway. On the other hand, in regard to a liquid flow path tube including a nozzle tube and an aerosol valve tube that structurally realizes stable and constant ejection of the content, there are methods using a flow rate stabilizer in the prior art. However, a flow rate stabilizer cannot be mounted in a flow path tube, requires adjustments, and is complex in structure and expensive in product cost, thus not allowing everyone to realize stable ejection.
Then, the present applicant previously developed a jet nozzle tube comprising a valve structure for mixing with the gas and realizing stable and constant ejection of the content and proposed the techniques in the patent application of patent documents 1 and 2. According to these proposed techniques, a valve structure is provided within a jet nozzle tube to enable adjustment of the flow rate by the diameter of a through-hole in the valve structure and to stir the content and the gas while they pass through the through-hole, whereby excellent effect on realizing stable and constant ejection of the content is obtained.
However, although yielding certain effect on stirring and mixing the content and the gas, the proposed techniques in the patent documents 1 and 2 cause foaming as a whole and fail to realize a completely stirred, and entirely uniformly mixed state. Consequently, the content eventually ejected is not in perfect mist to the extent of floating in the air.
The present applicant focused on the problem that the above prior art spray can or aerosol can fails to realize stable and constant ejection of the content, conceived of the idea for solving the problem by stirring and mixing the fluids (a liquid and a gas) that flow within a flow path tube, developed a technique for reliably stirring and entirely uniformly mixing the fluids (a liquid and a gas) within a flow path tube, and finally proposed the “flow path tube and jet nozzle tube and aerosol valve tube using flow path tube” according to the present invention.